Thursday, May 29, 2014

Twenty-three climate models can't all be wrong...or can they?

A new paper published in Climate Dynamics examines 23 different climate models to determine if any were able to hind-cast temperature, sea level pressure, and precipitation of the 19th and 20th centuries, finding

"not only do the models not agree well with each other, they do not agree with reality"

"the models arenot capable to simulate the spatial structure of the temperature, sea level pressure, and precipitation field in a reliable and consistent way"

"no model or models emerge as superior"

Nevertheless, climate scientists claim the entire global economy must be restructured on the basis of the overheated projections from models that are unable to reproduce the known history of climate over the past 2 centuries.

According to Steinhaeuser and Tsonis, today "there are more than two dozen different climate models which are used to make climate simulations and future climate projections." But although it has been said that "there is strength in numbers," most rational people would still like to know how well this specific set of models does at simulating what has already occurred in the way of historical climate change, before they would be ready to accept what the models predict about Earth's future climate. The two researchers thus proceed to do just that. Specifically, they examined 28 pre-industrial control runs, as well as 70 20th-century forced runs, derived from 23 different climate models, by analyzing how well the models did in hind-casting "networks for the 500 hPa, surface air temperature (SAT), sea level pressure (SLP), and precipitation for each run."

In the words of Steinhaeuser and Tsonis, the results indicate (1) "the models are in significant disagreement when it comes to their SLP, SAT, and precipitation community structure," (2) "none of the models comes close to the community structure of the actual observations," (3) "not only do the models not agree well with each other, they do not agree with reality," (4) "the models are not capable to simulate the spatial structure of the temperature, sea level pressure, and precipitation field in a reliable and consistent way," and (5) "no model or models emerge as superior."

In light of their several sad findings, the team of two suggests "maybe the time has come to correct this modeling Babel and to seek a consensus climate model by developing methods which will combine ingredients from several models or a supermodel made up of a network of different models." But with all of the models they tested proving to be incapable of replicating any of the tested aspects of past reality, even this approach would not appear to have any promise of success.